This study aimed to review the effects of the Coronavirus Disease 2019 (COVID-19)pandemic on the elderly. In this review, topics, such as the causes of COVID-19 severity in the elderly; psychological problems of the elderly; the relationship between underlying diseases and COVID-19 severity, and the comparison of COVID-19 with other pandemics were discussed.

This systematic review study was conducted in 2020 by searching international databases, internet search in the Google Scholar scientific search engine and ScienceDirect, Pubmed, Magiran, Cochrane Library, SID, WOS, and SCUPOS databases. We used the following keywords: “older adult, COVID-19, psychological problems, social isolation, abuse, and ageism”. Boolean Operator (AND, OR) was used for combination search without a time limit. The search strategy was limited to Persian and English articles. All search results, including titles and abstracts, were entered into Endnote. Original studies published in peer-reviewed journals were included in the current study. Articles with available full-texts were also included in this study. Letter to editor, gray literature commentaries and papers presented at seminars and conferences were excluded from this research. The Cochran checklist was used to evaluate the quality of the selected papers for experimental studies; the Greenhalgh checklist for quasi-experimental studies; the Strobe checklist for observational studies. if the checklist had all the criteria, it received a score of 2; if it covered part of the criteria, it received a score of 1, and if a study did not meet any of the criteria, it received a score of zero and was excluded from the study. PRISMA Statement has also been followed in drafting the article.

The results of the selected studies were extracted and the effects of COVID-19 pandemic on the elderly were explored in 8 parts, as follows: why COVID-19 is more common and has more complications in the elderly; mortality and complications of COVID-19 in the elderly; COVID-19and underlying diseases; psychological problems caused by COVID-19 in the elderly; abuse in the elderly and COVID-19; COVID-19 and age discrimination in the elderly, the comparison of COVID-19 with Severe Acute Respiratory Syndrome (SARS), Middle East Respiratory Syndrome (MERS), and influenza epidemics in the elderly, and elderly care was reviewed during COVID-19. The main results of these studies indicated that the outbreak of the COVID-19 has posed serious challenges to human life; however, one of the most critical challenges is the consequences of this disease in the elderly. The highest mortality rates, hospitalizations, hospitalizations in the intensive care unit, and complications from this disease are observed in the elderly [17]. Numerous older people stay at home for long periods, have difficulty accessing their daily needs; thus, they are exposed to social isolation, abuse, and age discrimination [18].

The COVID-19 pandemic presented numerous negative consequences in the elderly. Everyone must work to control the adverse consequences of the disease in the elderly, from government officials to individuals and families. The public media, especially radio and television, can play a crucial role in informing about COVID-19. Although about a year has passed since the outbreak of this disease, there remain many hidden angles about this disease and especially its effects on the elderly. To study the effects of the COVID-19 on the elderly and prevent the occurrence of negative consequences of this disease and other new pandemics that may occur in the future, further studies are required on the effects of pandemics on the elderly and approaches to prevent and control the related adverse consequences in the elderly.

All ethical principles are considered in this article. 

This research did not receive any specific grant from funding agencies in the public, commercial, or not-forprofit sectors.

All authors were equally contributed in preparing this article.

The authors declared no conflict of interest.
 

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